Low friction journal bearing



1951 T. J. NUSSDORFER, JR 2,542,051

LOW FRICTION JOURNAL BEARING Filed Aug. 1, 1949 THEGDOHE' J.NU$$DORFER,JH

Patented Feb. 20, 1951 UNITED STATES PATENT oFFics (Granted underamended 'April 30, 1928; 370 0.

This invention relates generally to journal bearings and specifically tojournal bearings for high speed rotation.

In plain journal bearings high starting torques are required to breakthe metal-to-metal contact of the shaft with the bearings.

Marring or scuffing of the bearing frequently occurs before an oil filmis established between the two parts. Roller bearings are frequentlyused in place of journal bearings but at high speeds they are subject tofatigue and breakage.

Full-floating bearings having floating sleeves are likewise subject todamage during starting, due to the failure of the sleeve to rotate whenthe shaft is rotated. Sudden applications of loads also damage thesurfaces of the shaft and the sleeve in such a bearing.

An object of this invention is to provide a journal bcaring having a lowstarting torque capable of high speed operation.

Another object of the invention is to provide a bearing using roller orball bearings at low speeds and operating as a journal hearing at highspeeds.

A further object of the invention is to provide a journal bearing havingno metal-to-metal contact of the bearing and shaft surfaces at periodsof rest or of low speeds.

Another object of the inventionis to provide a journal bearing having asleeve with roller bearings incorporated therein so that no damageoccurs to the sleeve or bearing surface when the shaft starts to rotate.

Another object of the invention is to allow the use of closer fitsbetween the shaft and bearing than is usual in journal bearings atpresent in use.

Other objects and advantages of the invention will hereinafter becomemore fully apparent from the following description of the annexeddrawings, which illustrate preferred embodiments, and wherein:

Fig. 1 is an isometric view partly in section of one embodiment of theinvention.

Fig. 2 is an end view in section of another embodiment of the invention,and

Fig. 3 is a side view in section taken on line 2-2 of Fig. 2.

Referring more particularly to the drawing in Fig. 1, a shaft IE] isshown in bearing housing H and separated therefrom by sleeves l2 and I6which are axially aligned by the overlap l where they join. Rollerbearings l3 fit into recesses 14 formed so as to prevent movementoutwardly of the roller bearings 13 under centrifugal force.

The roller bearings l3 support the shaft In in the act of March 3, 1883,as

the sleeves I2 and It in such a manner as to prevent metal-to-metalcontact of shaft ID with sleeves l2 and it at periods of rest and withsuch close tolerances that at high speeds of rotation an oil filmseparates shaft it from sleeves l2 and I6 and sleeves l2 and I5 fromhousing H and the roller bearings l3 are free of any pressure.

In Fig. 2, another embodiment of the invention is shown with shaft 20shown at rest in bearing 2| and the space between greatly exaggerated inorder that the relative positions of the parts be more fully understood.A dotted line 20' shows the position of the shaft 20 at normal and highspe d operation with oil or other lubricant (not shown) supporting theshaft 20 in the bearing 21 in the conventional manner.

Ball-bearings 22 in their races 23 are rotatably mounted on pinions 24mounted in the bearing 2! in the recess 25 therein provided and are heldon the pinions 24 by collars 26 and 21 as shown in Fig. 3. At positionsof rest the ball-bearings 2.2 and races 23 support the shaft 29 but arerelieved of any contact, stress or strain by the movement of the shaft26 to the position shown by dotted line 20' when it is rotated, due tothe oil or lubricant forming a film between the shaft 20 and bearing 2|.

Various modifications in the arrangement and proportions of the parts ofthe combination may be made without departing from the spirit and scopeof the present invention as defined by the appended claims.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

What is claimed is:

1. In combination with a journal bearing having a housing and a shaft, afree-floating hearing interposed between said housing and shaftcomprising a pair of bearing sleeves on said shaft adjacent one anotherand having an overlap and underlap formed in their meeting edges, androller bearings positioned in recesses formed in the overlapped edges ofsaid pair of bearing sleeves, said roller bearings having a diameterlarger than the thickness of either of said bearing sleeves but of lessdiameter than the thickness of said sleeves plus a load supporting oilfilm on each side of said sleeves separating said sleeves from saidhousing and said shaft in a free-floating condition.

2. A free-floating bearing to be interposed between a shaft and ajournalcomprising two sleeves positioned on said shaft adjacent one another anddimensioned relative to said shaft and said journal as to befree-floating on wedgeshaped oil films under conditions of high speed,and separate bearing means formed in the meeting edges of said sleevesadapted to support said shaft in said journal independent of either ofthe interposed sleeves under conditions of rest and relatively lowspeeds when no oil film is present.

3. A free-floating bearing to be used between a journal and a shafthaving a relatively heavy loading comprising two bearing sleeves of likediameter, a male shoulder formed on one end of one sleeve, a matchingfemale shoulder formed on one end of the other sleeve, a plurality ofarcuate recesses formed in both sleeves in the overlapping portionsformed by said shoulders, and a roller bearing positioned in each ofsaid recesses, the dimensions of said sleeves and said roller bearingsrelative to said journal and said shaft being such that said rollerbearings support said shaft in said journal at conditions of rest andprovide relatively friction-less starting and low speed rotation of saidshaft but are free of load-bearing contact with said shaft and journalat high rotational speeds of said shaft when a load-bearing lubricatinfilm of oil is formed and manintained between said sleeves and saidjournal and between said sleeves and said shaft.

THEODORE J. NUSSDORFER, JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,121,083 DeFerranti Dec. 15,1914 1,946,652 Wallgren Feb. 13, 1934 2,309,397 Illmer Jan. 26, 1943

